Unit transmitter and signaling system



May l1, 1948. M. w. MUEHTER 2,441,502

UNIT TRANSMITTER AND SIGNALING SYSTEM Original Filed Aug. 1, 1940 '7 Sheets-Sheet l INVENTOR M.W.MLIJEHTER 'ATTORNEY 7 Sheets-Sheet 2 M. W. MUEHTER ATTORNEY Original Filed Aug. 1, 1940 UNIT TRANSMITTER AND SIGNALING SYSTEM May 11, 1948.

May 11, 1948.

M. W. MUEHTER UNIT TRANSMITTER AND SIGNALING SYSTEM Original Filed Aug. 1, 1940 v 7 Sheets-Sheet 3 Non mokuumuc oznomu 33 m mmm .19. 8b.

v ;1 INVENTOR BY Z) 6 :9, -1'o ms. 1-

W. MUFHTER ATTORNEY May 11, 1948.

w. MUEHTER UNIT TRANSMITTER AND SIGNALING SYSTEM Original Filed Aug. 1, 1940 7 Sheets-Sheet 4 mmv 3 5%: P523 INDICATOR him. DELINQUENCY ON? Vow n .mm ohm mmm mmm N INVENTOR M. W. MU EH TER W6 v wE ATTORNEY May 11, 1948.

M. W. MUEHTER UNIT TRANSMITTER AND SIGNALING SYSTEM Original Fild'Aug. l, 1940 -7 Sheets-Sheet 5 FDO FDU INVENTOR M. w. MU E H TER BY a] f ATTORNEY May 11, 1948. M..w. MUEHTER 2,441,502

' UNIT TRANSMITTER AND SIGNALING SYSTEM Original Filed Aug. 1, 1940 7 Sheets-Sheet 6 FIG. 6

'C'LINE N.W. TRANSMITTER F.A.TRANSMITTER INVENTOR 'M.W. MUEH TER ATTORNEY May 11, 1948.

M. W. MUEHTER UNIT TRANSMITTER AND SIGNALING SYSTEM 7 Sheets-Sheet 7 Original Filed Aug. 1, 1940 ruL INVENTOR I M.W.MUEHTER BY m ATTORNEY ent invention isfto providel at the receiving at .tion, converting means ',for rerting "t ,s

Patented May 11 1943 UNITTRAN Am rican {Dis t. :T ph

" :rTERANn' s'IeNmLmG SYSTEM "M nimdiW-iMuehter tl xi l member 4,1 45

closed in applicants prior 'PatentN0.'2,109 ;273,

granted February 22, 1938. This application is a division of the applicant's application Ser.- l To. 359,622, filed August 1, 19510 noyvsU. .Bflteni; 2,390,222 granted Dec-A .1-945Qfor Unit transmitter printing and signaling systems.

The objects .of the invention .are -to provide separate alarm :and superyisorykcircuits, both working-in conjunction with .the same Sprinter and providing forprelEerential operationIoi alarm signal transmitters. This increases .the .i tlialcilifty of the more important, alarm s ervice, ,as alLalarin transmitters.areconcentratedon theirofincircuit which will, therefore, .be shorter and glss l exposed to troubles. Ifhe preferential jf eatureiinsures that alarm signals will. under n norir'ial or trouble conditions he givenifirst icon'sideration in recording, thereby eliininatin fipossible dejlajy insreception. I I 7 Automatic trouble adjusting means Lare nio- ,vided which, :in the case {of a break jofQone, 0125.11 of the three circuit Wires. adj st ltlietsystn} .for operation .under that .condition. -Inder'iefde'nt means are'iprovided .for the alarm and .t helsj'uperv'isory circuit and the-system -.is'. capable Qof K 'main- .taining operation -.of fal1 transmitters even. with breaks .in all of thetl ire'e lviii'es gof both circuits at the same time. aAutomatic gre'storat'ionj isgef- .fected as soon .asthe particular .circuit'jis jrepaired. Y

.Another. improvement relates .to the mode ..'.6f operation of certain typesjofjtransmittersllarrangedior' transmission of repeated alsrms gnals, as in the. case ;of.-.Wa,t er flow transmitters.

These transmitters :are arranged with Liacdde .wheel having an alarrn code'onlonesi'de. f the Wheeland a restoration.codeIon theothr' an as in thecase. of supervisory transmitters. lithe transmitter is also "arranged for .three ro1;1'nd

alarm signal operation, for instance. thefirst round will come .in as an alarmsignal, .the sec- ,ond as a restoration signa1' .and,' thethifr .ja ain as. analarm signal, eachlsignal being transmitted by onehalf of the wheel. (An.object.of' theljpresrestoration signal intoan alarm .sfig'nal d recording it as such, .iand perfcrm'same; an alarm (signal. via. ,tap out .the

s odeyonflthe nits. In case of .a .genuihfleirestoltaticn 1isigna1,'.0nly the 9Z1?i lfip i t qnflsig lal istransmitted, and the converting niea'nsflonot-loecome effective. Thus the signalperforrn as .required for a restoration 'si landf fails tp gtapout its code on the'gongs, 1 wh ch 'case th'e comfplete restoration signalwill 'a isn i t dat'f e hi L i 1 I con si cler athl y sirnfilifies theldesign of wt jsniitt ers fvyhich ouldotherwise 'require a double "setof code 'wheels and coding ippntacts and an additional geared controlling cam.

Various selective and other novel features will be gapparent from the following rebresentative writ en: 7..

'This systemis called a" unit" transmitter system because it makes use of an individual transmitter "for each"alarm "or supervisorydevice from which indications are reguired. Each transmitter is directl "attached to thefpa-rticular device-which "operate it. Ifhe various transmitters of a *systerriaretercorinec'tedby means of one or-in'ore thieewire mep circuits -Whi8horiginate at and return" to the control center.

The transmitters operate #in conjunction with control equipmentlocated at the control center in' a noni'nter'fering and -successiveumanner to record a signal on a printer recorder fat the con.- -trol center and to perform other :functions.

' The transmitters ar-e driven i by. current .im- .pu 'ses fror'nfithe-rdntrol station. "The basic'type of tran'smitte'rxis the supervisory type. alt-:has two codes' -arranged on ethe circumference. of its code wheel. One code is transmitted when ;:the associated device is zoperated ztogits alarm condiiti-on iand thewther'iwhen it is restored :to-its nor.- -.nial pos iti-on. The difference in zthe twotcodes consists in four1.;addition'al zteeth :in :the sec n zdigit fer the restoration si na Th im ls s transmitted are strong and Weak, girrrpulses =representin :sp se .=st .tins :Q 30. tra :mit-ter 'ris ,.-controll,ed.zthrough a i-transfer yearn .switc'h. :thewnosi nn o whic is rever ed 4 ng the-transmission of a sisn l. on on un t on 91 the transfer wi ch iaqr e a edih st e' su e vised device. Other transmitters will be referred to hereinafter. Codeinipulsesdrom the transmit- ;ters control the mp l e op rat d type car M olfstatibnp cygindicato is primed cons stin jm Ivvatiiretains-a time gm. titi mftii proper time interval, ;an (associated "transmitter 3 may be operated to record a delinquency signal on the tape. Operation of a night watch box will then reset the delinquency indicator and record a restoration signal.

All supervisory signals, that is, signals from sprinkler supervisory devices and delinquency signals, are arranged to register on a totalizer which is advanced one step when one of the above-mentioned devices runs in an alarm signal and is moved back one step when one of the devices is restored to normal. It thus indicates at all times the number of abnormal supervisory devices.

A ground detector relay is connected to the center of the ungrounded battery. The other terminal of the relay coil is connected to ground. A ground on any external circuit will operate this detector relay and give a lamp and buzzer signal. The buzzer can be silenced by turning the associated lamp switch. When the ground is removed from the system, the light goes out and the buzzer rings again until silenced by turning the switch back to normal.

Since no other ground exists on the system except through the high resistance coil of the ground detector relay, a single ground will not interfere with the operation of the system especially as the ground connection is removed from the detector relay while a signal is being transmitted.

In the drawings, the figures show diagrams of the system, transmitters and signals.

Figs. 1 to together show the control station, printing recorder and two types of transmitters.

Fig. 1 shows the supervisory circuit and transmitters.

Fig. 2 shows the alarm circuit and transmitters.

Fig. 3 shows principally the control station means for supplying the impulses to the transmitter circuit and the type carrier setting means. i

Fig. 4 shows principally the routing relays for supplying the impulses to the respective typecarrier setting means.

Fig. 5 shows the printer and totalizer.

Figs. 6 and 7 respectively show the night-watch and fire-alarm transmitters.

Figs. 8 to 13 are diagrams representing strong and weak impulses of types of signals as titled, the upper solid line portions representing strong impulses, the dotted lines representing weak impulses, the number stated being the transmitted number.

Fig. 14 is a diagram showing relative placement of the several figures of the drawing to form the complete circuit diagram. The basic principle of the transmitters and their operation are similar to those disclosed in the above-mentioned Patent 2,109,273.

The mechanical elements of the printer are similar to well known types of printing recorders and to those shown in my prior Patent 2,126,025, August 9, 1938, and the patent to Johnson et a1. 2,172,511, September 12, 1939.

Supervision The supervisory circuit for the common and starting lines of the supervisory transmitter circuit can be traced as follows: From plus battery through contact 31 (upper left of Fig. 3) over conductor I38, out over the ST loop and back to the control center, through make contact IIlI of relay I25, through relay I02 over the C line to minus battery (Fig. 1). Relay I02 is normally 4 held energized through this circuit to thereby supervise the ST and C lines.

The supervisory circuit for the R line can be traced from plus through the right hand winding of main starting relay I03 (upper right of Fig. 1) back contact I34, left hand winding of relay I03, through the R line, and corresponding contacts Hi5 (Fig. 1) of the line transmitters, back to the control center through make contact I06, through the middle winding of relay I63, through the coil of of relay IEiI (lower right of Fig. 1), over conductor I08, through contact 362 (upper part of Fig. 3) to minus battery. Relay IIl'I (Fig. l) is normally held energized in this circuit to thereby supervise the R line. Although current is fiowing through all three windings of relay I03, it is to be noted that the middle winding has a number of turns equivalent in effect to the sum of the other two windings of relay I03 and is connected opposingly so that the efiect on relay I03 is neutralized.

Similar supervisory circuits can be traced for the alarm circuit involving supervisory relays 202 and 20! at the lower right of Fig. 2, as will be evident from the above.

Transmitter start The transmitter of Fig. 1 is similar to that of applicants Patent No. 2,109,273, above referred to, and comprises a pair of stepping motor magnets, Iil and II, adapted to actuate the armature I2. A shaft carrying a master cam I4, a transfer cam I5 and a code wheel I6, which may be toothed on the alarm side as shown in Fig. 8, and on the restoration side as shown in Fig. 9, is rotated, step by step, by a .pawl and ratchet, not shown, under the control of armature l2.

Assuming, by way of example, that the operation of the supervisory transmitter of Fig. 1, shown connected to the supervisory line ST at the upper left hand side of Fig. 1, is initiated by actuation to the right of the transfer element of the device switch I09 of the associated device to be supervised, a circuit will be closed from the ST line, where plus polarity of the battery is available at contact 3Ill (Fig. 3), as has been explained, through the device switch I09, the normally closed contact I II] of the transfer cam contact, through the normally closed master cam contact II I of switch I26, and the right hand magnet coil of the transmitter to the C line where minus polarity is available as shown. The transmitter magnet is energized and attracts its armature closing its contact I I2 and engaging the next tooth of the ratchet wheel preparatory to advancing it one step when subsequently deenergized. By closing contact I12, the R line is connected through contacts I05, I05, H2 and the armature I2 to the tap of the right hand transmitter coil and the current flow in the out side of the R line is considerably increased. This has the eifect of increasing the current through the two outer windings of relay N13 to such a degree that relay I03 will pick up.

Relay I03 looks from plus in through its right hand winding, contact I I3, resistor I I4, over holding conductor I I5 and through contact 303 of relay 3I5 to minus. Relay I03 also energizes relay II6 from minus through contact II! and its middle winding. Relay II6 opens the running line at contact IM and also looks in from plus through its left hand winding, make contact I I8, resistor I I9, to holding conductor I I5. The break a lamp 11' through an obvious circuit.

:2914-1 ,ees

Start .01 nursin relays The main pulsing .relay ;is .304 which operates .in conjunction with'relay'305. "These :relayastart their operation as soon as contact 20 of :relay H6 closes a circuitiromplus over conductor I2I, through contact 335' or relay .315. over conductor :30], through contact 404 :of -:relay 432, :over

movesflthe shunt .from the left-hand -.winding .of relay 36-5 permitting it to .operate .from :m'inus through resistor 3D, left hand Winding of 3.05 to plus obtained from conductor 10.2 as traced above. When coritactBLI of relay 305 .-closes,.the

winding of relay :304 is shunted'out .and relay 304 deenergizes with a slight :delay. At this ;time acircuit is closed from plus throughcontact 3Ie2 of relay 335, contact 3I3,conductor33l4f, aback contact 222, conductor 3Ii4, contact $123,. over conductor I24 and throughxthe .coil .of the supervisory masterrelay 3 I5 and.contact:3:I fiito minus. Relay 3I5 operates. This relay closes a locking circuit for itself through contact 3I'I to plus over conductor 462 to keep itself energized when contact-3l2 of relay 305 or-contact=3I'3-o1 relay 3014 opens. By openin its contact 301, relay' 3I-5 removes plus battery from the starting line ST causing the transmitter previously operated to release its armature and advance its ratchet wheelone step. It-willbe'noticed-that this happens-after a time delay following the operation of relays I33 and 416, giving sufiicient time"=to the transmitter -magnet'to operate properly and for other functions which will be subsequently explained. The opening of the starting line causes the release of relay I02.

The'first step of the transmitter changes the position of the master'cam contacts to the operated position. The right hand magnet coil-ofthe transmitter is now connected to-the"out'side of the running line R-through-contact 4-25 of-switch Mwhile the left hand magnet coil is connected to the in side of the running line R through Following the release of the main impulse relay 304 which energized relay 3 I' 5, the-coil-of relay 305 is shunted by back contact 309 .causing relay 305 to release withaslightdelay. With contact 3 of relay 305 opening, "the shunt is removed from relay 304 permitting it toenergize again. At this time an impulse is transmitted to the transmitter, the circuit of which'zcan be traced as follows: from plus through :makecontact 3l8 f relay 304, the coil of marginal operating relay 3l9, conductor 3I'9', contact 320, over conductor- 32L make contact 1521 of .relay "I03, left hand Winding of relay 103, the R line, in series with the master cam contacts similar to I of intermediate transmitters, if there are any, through contact I25 of the operated transmitter and its'right hand magnet coil to the C ime and'minus. The transmitter magnet is thereby energized. As the code wheel contacts of the transmitter are not yet closed, this'impulse will However, enough current conductor .402, through :resistor $3.08 iandth'eilefthand Winding of relay 304 .to'minus. Relay 330-4 1 operates and by opening its backcontact 1309 .re-

fiows through the left hand :winding io'frelay i103 to 'k'eep it-energized. It will n'ow'bezshown that :at this time rel ay l 03 hlas to depend :on thi's left han'd windingiforits energization. As'the time :relay-3I'5 is energized, the locking circuit :for the right hand. winding of relay 103 is transferred fromminus-battery throughcontact 3il3 of relay *315 to minus battery through contacts .322 .of relay 315 and 324 of relay 3%, contact 323 of relay-305 in multiple with contact; 3Z41being open at thattime. lt maybe noted'that contacts 303 and 322 are 0f the make-before-break type .thus preventing momentary interruption of the holding cir'cuit of relay 103 when relay '3I5 locks up. A short time after relay 334 is reenergized, at the time of the transmission'of an impulse'over "the R line, re1ay 305 is also reenergized asrelay 304 again removes the shunt from the winding of relayfl305. Both contacts 32-3and324 are thus 'openeddepriving the right hand winding of re- -l-ay I03 of current. However, asindicatedabove relay I03 stays energized because of the current .fiowing through its left hand winding.

Relay 305 energizing againshunts the-coil-of main impulse relay 304 which-drops out with a slight delay. This successiveoperation of relays 30l4 and 305 now-continues for the' full "time-of the signal transmission. *Everytime. 304 releases, the line impulse is interrupted by the opening -cifitscontact 3IB,- and the transmitter releases advancing its ratchet-wheelonestep. -Since back contact 324 of impulse relay 304 is arranged to close prior to the opening'of front contact 3I8, I

the lockingcircuit for relay I03 is not-even momentarily 'interrupted. I

First coding impulse "In this way the transmitter will be operated step by step until the first tooth of the first digit-of the code wheel closes itscontactsshunt- .ing the upperportions .of the transmitter magnet coils. The .next impulse will, therefore, be of considerably reate'rintensity and will be a signal iimpulse sufficient -to:operate the marginal relay 3I 9. Byclosing its make contact 325, relay 3I'9 energizes the coding'relay 403 from minus .over conductor 326, through its two windings in series and to plus at conductor 301. Relay 403 looks in from minus through its contact 404 and its left hand winding to plus over conductor 30H, which is now connected to plus as above explained. Fig, -8 shows an example of a supervisory alarm signal.

Firstlimpulse .to printer "When impulse relay 304 subsequently releases, the first-digit type carrier=stepping magnet 'P'S'I, Fig. 5, receives an impulse from plus through back contact 321 of 'relayf304, over conductor 3-28, contact :405 of relay 403, back contact-436 'of the first shifting relay 432 (bottom of Fig. 4) conductor 401 arldthe coil ofthe first stepping magnet PS1 to minus. The-latter advancesits ratchet wheel one steparid brings the stepping wheel retaining pawls' into operative position-to prevent retrograde movement and also closes latch contact L which stays closed until the printerhas been reset to normal.

Sendingcodingimpulse from supervisory trans- ,mz'tter When impulse -relay 304 is energized for the next line impulse, -a circuit is 'a-lsoclosed from plus through make 'contact'flc ofrelay;301'l, over -'-wir=e :330, break contact 408 of relay 422;:break "contact 409 of relay 432," right hand winding of Winding of the first converting relay 411 to minus. Relay 441 is thus operated and locks in from minus through its contact 4! and righthand winding to plus over conductor 369.

When relay 304 subsequently releases, a circuit is closed from plus through its contact 333, over conductor 334, contact MS of relay 410, the left hand winding of relay 410, over conductor 420 and through contact 335 of relay 3l5 to minus, thereby holding relay 410 energized. It is to be noted that contacts 329 and 333 of relay 304 are of the make-before-break type so that the circuit for the left hand winding of relay 4l0 will be closed before that of the other winding is opened. Another circuit is closed at this time from plus at conductor 334 through break contact 421 of relay 432, make contact 422 of relay 410 and through the right hand winding of relay 423, Conductor 420 and contact 335 of relay 315 to minus, thus operating relay 423.

At the same time another impulse is transmitted to the first stepping magnet PSI, of the printer over the previously traced circuit through back contact 321 of relay 4304.

The third and following code impulses of first digit When the next impulse is transmitted to the line circuit back contact 333 of relay 304 is opened deenergizing the left hand winding of relay 410, and relay 4|0 releases since the previously traced operating circuit through make contact 323 of relay 334 and back contact 408 of the third shifting relay 423 for the right hand winding of relay M is no longer closed. However, relay 423 remains energized from plus at conductor 330, through contact 424 and the left hand winding of relay 423 to minus at conconductor 4. When relay 304 releases again, another impulse is transmitted to the first stepping magnet PSI of the printer. The former operating circuit of relay 423 is now open at contact 422 of deenergized relay 4I0, but another circuit is closed instead through contacts 445 of relay M0 and 446 of relay 423 to plus at conductor 334. The following impulses of the first digit will have no other effect except operating the transmitter and the first stepping magnet of the printer for additional steps. Relay 423 will remain energized through the right hand winding during the time the relay 304 is deenergized and through its left hand winding during the time relay 304 is energized.

First shifting space When the space following the first digit group of teeth is brought into position opposite the coding wheel contact-s, these will remain open and the subsequent line impulse will be of low intensity, as indicated at the sixth impulse of Fig. 8. This low intensity impulse is not capable of operating marginal relay 3l9 and the low intensity impulses correspond to the absences of impulses in most other systems,,and are her-' in referred to as spaces as contrasted with the stronger signal impulses. Both windings of coding relay 403 will now be connected in multiple as follows: the right hand end of the winding is connected over conductor 326 through contacts 335 of relay 3I9 and 336 of relay 304, to plus at conductor 402, the left hand end being connected to plus at conductor 301, while the common in the middle is connected to minus through contact 404. The flux set up by the two equal windings will be of opposing direction neutralizing one another and cause relay 403 to release.

When relay 304 subsequently releases, a circult is closed from plus through 333 of relay 304 over conductor 334, through contacts 425 of relays 403, 426, of relay 410, 421 of relay 423, 428 of relay 432, resistor 429, conductor 404, and through the right hand winding of the second shifting relay 430 to minus, operating relay 430. No impulse is transmitted to the printer at this time as contact 405 of relay 403 is open.

Second digit The next impulse transmitted over the line will again be of a greater intensity as the first tooth of the second digit operates the code contacts to the closed position. Relays 310 and 403 are operated as before. The above traced cirouit of relay 430 is interrupted at this time but another circuit is closed for its other winding from plus at conductor 330 through make contact 43'! of relay 430, the left hand winding of relay 430 to minus at conductor 4! I, maintaining relay 430 in an energized position. At the same time, a circuit is closed for relay 432 from plus at contact 43l of relay 430, through the left hand winding of relay 432 over conductor 433, through contact 331 of relay 345 over conductor 4 and through latch contact L in the printer to minus, operating relay 432. This relay locks in from plus through its other Winding and contact 434 to conductor 4 and contact L. Contact 40I opens but multiple contact 435 of relay 423 being closed, the circuit for the pulsing relays and relay 315 remains closed.

When relay 304 subsequently releases, an impulse is transmitted to the second stepping magnet PS Z of the printer from plus through contact 321 of relay 304, over conductor 328, through make contacts 405, 436 or relay 432, 431, 438, over conductor 439 and through the coil of the second stepping magnet PS2 to minus. Relay 430 is maintained energized through its right hand winding but now from plus at conductor 334 through make contacts 440 of relay 403, Ml of relay 430, and 442 of relay 432.

Subsequent code impulses will operate the transmitter and second stepping magnet of the printer for additional steps but no change in the routing relays 4 I 0, 423, 430, 432 will occur until the space following the second code digit causes the next shift impulse, relays 403, 423, 430, 432 remaining energized in the meantime.

Third digit Relay 403 is deenergized when the low current impulse following the second code digit is transmitted over the line. When relay 304 releases following it, relay 430 is deenergized as the circuit of the right hand winding is opened due to the opening of contact 440 of relay 403.

When the next impulse is transmitted to the line circuit, the first tooth of the third digit closes. the code wheel springs of the transmitter again, causing relays 3l9 and 403 to operate. At. the! same time the relayv 4| is. reenergized from plus at conductor 33'0lthrough contacts 443.

of'relay 4'30; contact 4440f relay 432;]and the right hand winding of relay M0 to minus at conductor 4H.

When relay 304' subsequently releases, relay 4 lfl'remains energized through its left handwinding, andlcont'act 410 as before. At the same time, relay 423 isv deenergizedsince the circuit for its right hand winding is open at' contacts 445 of relay 4l0as well as 42! of relay'4-32. Contact 435' of'relay 423 is opened butthis has no effect since it is in multiple with contact 441 of'relay 4|0"whic'h is now closed, maintainingthe operating circuit of thepulsing relaysand'relay 315" closed; Furthermore, an impulse is transmitted to the third stepping magnet PS3 ofthe printer which can. be traced from plus through contact 3210f relay 304, over conductor 328, through contacts 405, 436", 448', over conductor449, and

Following the third digit, a space is'e'ncountered by the code springs of'the transmitter code' wheel causing a low current impulse on the line,

not capable of' operating relay 31 9. Relay 403' releases. When relay 304 subsequently deenergizes, relay 430' is energized? again from plus at conductor 334 through contacts 425 ofrelay 403; 448 of relay 410, 442'" of relay-432; resistor 429 and right h'and'winding of" relay 4'30'to minus.

When the next impulse is transmitted over the line", the first tooth of the f'o'urthdigit will cause operation of relays 310 and 4032 At the same time relay= 4H) is deenergized-as the circuit for its right han'd' 'winding: is open at back contact 443-- of relay: 4302 Relay- 430, however; remains energizedl'through its make contact 431: as earlier described.

Contact 44-1 of. relay-410 is now open but is shunted by contact 449 of relay 4'03 thereby maintaini'ng the circuit for the pulsing relays and relay 3l5 closed.

When relay 304* subsequently releases, an impulse istransmittedcto. the fourth steppingmagnet PS4: of the printer from plus through back contact 321-. of relay 30.4", over conductor; 328- through. contacts 4:05 of relay 403 436- of relay 4-32 43 1: of relay 43.0,. 45.0" of relay 423, conductor. 4K! and the coil of the "fourth stepping magnet BSA-"to minus. The following impulses of the fourth digit: advance this 'magnet and the' moved. With. the subsequent release of relay 365, there is an alternative path. from ,1 plus through: its contact 342 and. 333 (of relay 34:5) for energizing-the pulsing relays. and, the enere gizing: circuit for relay 315- isopened;at}contact:-

:50! together with contacts 501 and 502.

the chosen designations of the printer wheels the.

, 1Q. 3E2 causing the pulsing relays to cease operation and relay 3l5 to release. 3|5 opens. andremoves plus from the holding conductor 36.9 offrelay 411, but plus is still be- .ing. supplied by contact 4520f relay 430 which is stillenergized from, plus at conductor 334 through contacts, 453' of relay 423, Ml of relay 433, '442 of relay 432, resistor 423 and the right hand winding of relay. 430' to minus. At the instant relay 305 releases, a circuit is closed from plus through contact 333; conductor 334, contacts 425 of relay. 403; 426 of relay 440,. 454 of relay 423, over conductor 455, through contact 340' of relay; 305, over conductor 34%|, through contact 456 of relay 430, over conductor 451,

throughthe printer cut-out contact PC and the, printer magnet PR to. minus. The printer mag net is energized causing the signal already set up on the four typewheels of the printer to be printed on the tape.

The totalz'zer At this time it may be explained that the sec- 0nd typewheel of the printer operates a. cam For cam 501' isso arranged that normally, and if magnet PS2 is-operated for 1, 2, 3 or 4 steps,'con tact 50! isclosedand 532. is openand if operated for more than 4 steps, contact 532 is closed.

and 50] is open. Assuming that magnet PS2 was operated 5 times (correspondingto an alarmsignalwith 3 as thefirst numeral of the device number) the following circuit can be traced at the time the'imprint magnet is operated: from conductor 34! to. which. plus polarity was traced above, through contact458. of relay 430 over conductor 459;. through contact 50.! and the. adding.

magnet 510 of a so-called. totalizer over conductor 505,. through. contact. 453 of relay 4", conductor 454-and contact 342" of relay 3| 5' to minus, operating the. totalizer. The totalizer is av step-by-step device operating a common indicator shaft. in. either direction, dependingon- Whether actuated by one or. the other of its mag.- nets. supervisory devices in. an abnormal condition at. any giventime. The second? typewheel prints simple numbers in its first printing positions and duplicates these numbers with theindication Rest. meaning restored at the other positions. Therefore, when thesame transmitter which sent the signal of Fig. 8 sends a. restoration signal (Fig. 9),- the second digit would have 7 impulses. The second typew-heel would then bring Rest. 3 into. printingposition. The subtracting mag.-

net of the totalizer would then be energized.

instead of the. adding magnet, setting the indicator. back one step. a

1A. multiple circuit may also be traced from plus. at conductor 459 through conductor, 459" the resetting. magnet 465' of. the night watch delinquency indicator, which will be mentioned againv later, over. conductor 456 and through the lower winding of'special' attention relay 343,,to minus. Mag-net 465 does. not operate in thiscircuit because of the high, resistance of the winding ;of relay 343; but thisrelay does, locking in fromplus. through its upper winding, its contact 344v and contact. 3.45 of, relay 305 to minus. Througnobvious circuits relay 34:; operates a light 3481 and. a buzzer 348 by closing contacts 346 and 3411 Thisrelay will-stay energized and maintain its visual andTaudible signal until the attendant Contact 334 of relay It is used to indicate. the total number of operates a key switch operating a transmitter which may be similar to that of Fig. 6 and which records an acknowledgment signal on the tape. Contact 345 of relay 305 is opened by hand or may be opened by this transmitter momentarily by means of a cam 345' (Fig. 6) on the transmitter shaft which operates near the end of the transmitter cycle, causing relay 343 to release. This switch and cam would not be present on the night watch transmitter mentioned hereinafter.

When the imprint magnet operates, it closes its contact 503 and connects minus battery over conductor 504 to the left end of the right hand winding of relay 430 causing a shunt across this winding and making it release with a slight delay. Contacts 456 and 458 open and deenergize the imprint and totalizer magnets, and the armature of the imprint magnet releases and operates means which move the paper tape forward one step.

Opening of contact 452 removes plus from looking conductor 369 of relay 4I'I, causing it to release.

A circuit is now closed from plus at conductor 34I through contacts 460 of relay 430, 4'6I of relay 432, conductor 362, coil RL of the release magnet in the printer, through contact 506 to minus, operating the release magnet. This magnet releases and restores the printer typewheels to normal and opens latch contact L. The latter causes relay 432 to deenergize by opening the circuit of its right hand winding.

When contact 40I of relay 432 closes the circuit of the pulsing relays, these will start their operation with the energization of rela 304.

It will be noted that the operation of the pulsing relays has been stopped until the completion of the printing and clearing operations of the recorder. This feature makes these operations reliable and independent of the speed and impulse duration of the pulser and in conjunction with the printer cut-out contact PC, which is arranged to open automatically when the printer head is lifted, for changing paper for instance, prevents further signals from going is without the possibility of mutilation of line impulses, which could occur, were the cut-out switch connected directly into the pulsing circuit; When relay 304 operates for the first time after restora tion of the printer, no impulse is transmitted to the line as contact 320 of relay 3I5 is open. However, the starting relay I03 has been maintained energized as its locking circuit through its right hand winding, its contact II3, resistor H4 and conductor II5, has been transferred by contact 303 of rela 3I5 directly to minus.

Subsequently, relay 305 is energized and 30 4 deenergized again. At this time the original operating circuit for relay 3I5 is closed from plus through contacts 3I2 of relay 305, 3l3 of relay 304, conductor 3I4, contact 222 of relay 2I6, Fig. 2, conductor 3I4, contact I23 of relay II6, conductor I24, coil of relay 3I5 and back contact 3I6 of relay 3I5' to minus, unless a signal is waiting to be recorded on the alarm circuit, in which case contact 222 is opened and 223 closed, as will be explained with more detail later in connection with the preferential arrangement for alarm signals.. Assuming that this is not the case, relay (H5 is energized and again locks in through its contact 3II to plus again available over conductor 402. Impulses are again transmitted through contact I21 of relay I03 to the R line circuit as contact 320 of relay 3I5 is now closed. Except in cases where there is only one space between the last tooth of the fourth digit of the transmitter code wheel and its following home position, the transmitter is at this time still in the running condition, i. e., with the master cam contacts in the operated position. The transmitter will again be operated by the line impulses which, however, will all be of low intensity since no more teeth are provided on the code wheel. Eventually the transmitter reaches its home position where the master cam I4 and its contacts are restored to the position as shown in the drawing and the R line circuit will be open except in a case where another transmitter is already connected to the R line waiting to trans-- mit its signal, as will be explained later. The transmitter just operated is now again in its home position except that its transfer cam in the meantime has operated the transfer cam contact to the other side to be ready for a new start when the device switch is thrown back. In transmitting its signal, the transmitter code wheel has completed approximately one half revolution.

These above mentioned resetting impulses have no effect on the control center relays and printer. When the transmitter has disconnected itself from the running line and provided no other transmitter is already waiting on the R line to send its signal, the impulse circuit will be open when the next line impulse is transmitted. Relay the middle winding of relay I03 is also open, as

contact 302 of relay 3L5 is open. Relay I03 deenergizes and causes relay I I6 to release by opening contact II I and breaking the circuit of the center winding of H6. The common circuit of the pulsing relays and relay 3I5 is at this time maintained energized from plus through contacts 3I2 of relay 305 and 339 of relay 3I5 in series but is opened at the time relay 305 releases the next time. When this happens, relay 3I5res'tores to its normal deenergized position. The line circuit is now normal again and relays E02 and I0! pick up.

All relays are now in their normal position except relay 343 (right of Fig. 3); as explained above, it is deenergized by the operation of the acknowledgement transmitter.

The system is now ready for a new operation. If, for example, the device switch of the abovementioned supervisory transmitter of Fig. 1 is thrown back to the position shown, a new starting circuit is closed through the other side of the transfer cam contact starting a new cycle in the manner described above. The only difference will be that a different code is transmitted, the restoration code having four more impulses in the second digit, as shown by Fig. 9, bringing the designation Rest. in position to be printed.

Night watch transmitter The operation of night watch transmitters (Fig. 6) which are also connected to the supervisory circuit, is the same as that of the supervisory transmitter as explained above except for the following points:

As shown by Fig. 6, the starting circuit is closed by a latch contact II. This contact is closed when the associated latch I2 is tripped as 13 the watchman operates the box with his 13. The latch contact is restored to its normally open position by a restoring cam 14 near the end of the signal. As before mentioned, the switch 345 and cam 345' is not used when this transmitter is used as a night watch transmitter.

The first digit of the code of this transmitter consists of a single tooth followed by an extra space in addition to the ordinary digit space. As with the type wheel designations as chosen, the second wheel will ordinarily not be used for night watch signals, there will then be a third space (see Fig. causing no impulses to be directed to the second printer wheel and a blank space on the tape in that particular column. Thiswill be apparent from the following description. I

The operation for the first high current impulse is the same as above described, the first printer stepping magnet receiving one impulse bringing the designation night watch station into printing position. When the space is encountered during the transmission of the next line impulse, however, relay 4|! is not energized, as contact 33I of relay 3l9 is open, and will not subsequently be energized during this signal as its circuit will be open at one or the other of the series contacts, 414, M3, M2 and 411, all of which are only closed simultaneously during the transmission of the second line impulse. However, routing relay 410 is operated at this time over the same circuit as previously explained for supervisory transmitters. When relay 304 subsequently releases, relay 423 is energized'likewise as before. No impulse is, however, transmitted to the first stepping magnet as relay 403 is deenergized and contact 405 open.

Due to the above mentioned additional space after the first tooth on the code wheel, the next line impulse is likewise of low intensity. However, relay 410 is deenergized at this time in the same way as explained for supervisory signals. When relay 304 subsequently deenergizes, relay 430 is energized likewise as before. As the following line impulse is again of low intensity, relays 319 and 403 will not operate but relay 432 will, through the same circuit as above traced for supervisory signals. Contact'405 of relay 403 being open, no impulse will, however, be directed to the second printer wheel when relay 304 subsequently releases. At that time relay 430 is deenergized as described above after the second code digit of supervisory signals. The following third and fourth impulse groups also operate in the same way. At the time the imprint magnet is energized, however, the circuit to 'the totalizer is not closed as make contact 463 of relay 4|! is open. A shunt is also applied to the lower winding of relay 343 from minus through contact '342' of relay 315', conductor 464, contact 461 of relay 4|! to conductor 466. Thus, when plus is applied overcontact 458 of relay 430 to the lower end of the coil of the night watch delinquency indicator reset magnet, as previously described, relay 343 fails to operate. The resistance of its winding being eliminated from the circuit of the reset magnet 465, current of sufficient intensity will flow to operate it and reset the night watch delinquency indica'tor'back to zero. The Hopkins Patents No. 1,942,814 and No. 1,942,815 show delinquency indicators. As the delinquency indicator itself does not form part of this invention, it need only be mentioned that the minute impulses magnet 468 operates a pawl mechanism which advances the main movable element of the delinquency alarm toward an alarm position which will be reached if the night watch transmitter does not operate and energize reset magnet 465 (as explained above) in' time to prevent it. If the alarm position is reached, said movable element will operate a spe cial transmitter constructed and connected as in Fig. 1. To this end, said movable element will push the leftwardly biased transfer element of the starting switch to contact I09, and record a delinquency alarm on the tape and on the totalizer, as above explained of the supervisory transmitter.

Should the night watch signal subsequently come in, the delinquency reset magnet 465 will be energized, allowing said movable element and said transfer element to restore to normal.

Fire alarm transmitter The fire alarm transmitter shown in Fig. 7 is very similar to the night watch transmitter. Being one of the alarm transmitters, it is connected to the alarm circuit. It is actuated by a latch arranged to close contact H. The latch 12 is tripped when the operator pulls on the lever 72a provided on the front of the station housing 121). This breaks the glass rod 120, and then withdraws the plunger 12d against the cam 12c of the latch 12, thus releasing the latch 12. The spring 12f restores the lever, and the switch "H is restored to the normal position by the restoring cam 14 after transmission, even though the glass rod has not been replaced. Subsequent operation can be obtained by pulling on the lever, even though the glass rod has not yet been restored. This transmitter is equipped with gears to provide for a multiple round signal, i. e., the restoring and master cams and contacts are operated by a geared shaft which is geared to the main or motor shaft in such a way that said contacts will be maintained in the operated position' for six consecutive signals or three revolutions of the main or code wheel shaft, both sides of the code wheel having exactly the same code.

When the transmitter is started, due to the closing of the latch contact, it will operate the system in a similar way asexplained above for the supervisory transmitters except that the operation will involve starting relays 203 and 21 6 and relays 202 and 201 (Fig. 2) instead of I83, H6, I02 and I01 (Fig. 1).

Start of pulsing relays for alarm signals The pulsing relays are started by applying plus through contact 220 of relay 2I6, conductor 22!, contact 306 of relay 3l5 to conductor 307 and 402; Again relay 304 isenergized, then relay 305, then relay 304 is deenergized closing a circuit from plus through contacts 3l2, 313, conductor 3!4 ,'contact 223 or relay 216, conductor 224, and through .coil of relay 3i5 and contact 316 to minus, operating master alarm relay 315 which locks in to plus through contact 3", conductor 307, contact 306, conductor 22! and contact 220 of relay 216. Impulses are now transmitted to the running line R, of the alarm circuit through contact 320 of relay 3l5, the conditions exactly corresponding to those of the supervisory circuit as explained above.

The first digit of the fire alarm code consists of two teeth followed by a single space (Fig. 13). It will be remembered that the fact whether or not there is atooth after' the first tooth of the first digit 'is decisive for operating the relay 4|! or not. As there is a tooth in this case after the first one, the 4 I! relaywill be operated, thistime through cntact36l' of relay3l5, and conductor 389, insteadof contact 361 as previously. Otherwise the operation is the'same as explained-above for supervisory transmitters with contact 335 taking the place of 335.

Automatic speed change for gong operation When relay 433 is operatedthrough resistor 493 and its right hand winding at the termination of the lowcurrent impulses following the first digit; relay 350 is operated in multiple therewith through contact 433 of relay 4!! over conductor 35!, its upper winding over conductor'356 and through contact 531 (Fig. 5) to. minus. This contact is operated by a cam coupled to the first type wheel. Normally and in the first and second position, sometimes also in the third position, contact 53'! is closed and open in the other positions. Relay 359 locks in from plus through its contact 352, its lower winding, conductor 4| I and through the printer latch contact L to minus until the printer has been restored after recording the signals. By closing contacts'353 and 354, relay 353 connects another winding of relays 304 and 305 in multiple with their normal operating windings. The pulsing speed of the relays is thereby reduced to a degree as consistent for gong operation. This for the following reason: The timing of theimpulses depends mainly on the release time of the relays. As the release is caused by reciprocal shunting of the windings, it is slow on account of the induction effect whereas the pickup is fast, representing a small percentage of the pulsing time. Now the decay of the flux in a shunted magnet follows the law =oe* (where 450 is the flux before shunting, t the time in seconds, R the resistance and L the inductance of the winding) or where n is the number of turns and c is a con stant for a given relay). This formula shows that the release time of a shunted relay canhe changed greatly by changing the resistance or number of turns of its winding or both.

With relay 35G operated, the impulses to the second, third and fourth stepping magnets of the printer will also operate gongs. The circuit for these stepping magnets was traced above through contact 436 of relay 432. From there a branch circuit extends over conductor 4653, contact 355 of relay 353 and through the gong or gong conductor 351 to minus.

Otherwise the operation is as explained for supervisory transmitters except that relay 432 is operated during the first high current line impulse of the second digit through contact 349 'of relay 3I9 instead of 33'! of relay 3I5.

At the time theimprint magnet is operated, the circuit to the totalizer is not closecLas contact 342' of relay '3 I 5 is open. This contact also keeps the shuntacross the lower'winding of relay 343 open, so it will operate and give a, special attention signal.

Alarm transmitter maintained in operation after printing It will be recalled thatrelay 3I5 is deenergized at the time of theprinting operation. This is not the case with -3I5' as its looking circuit through contact 13H is connected directly to conductor 38'! which is now connected to plus at contact 220 of relay '2I6 .asexplalned. However, the operanat log nat log tion of the pulsing relays is stopped in the same way at this time as only relay 432 is energized and the contacts 41 of relay-432, 443 of relay 433, 447 of relay 4H1 and'435 of relay 323 are all open. The pulsing relays will, therefore, immediately start to transmit impulses over the line circuit when contact 40! of relay 432 closes following the printer resetting operation at which time the latch contact L opens and causes relay 432 to release. The locking circuit of relay 35!! through conductor 4 II and contact L, as explained above, is likewise deenergized. The higher speed of pulsingwill then be resumed. At the same time, a circuit is closed from plus through contact 33? ofrelay 3 I 5,- conductor 339, contacts M I of relay 433, M2 of relay 432, M3 of relay 4Z3, 4'53 of relay 4 l 0 and 4H of relay 4 I I and through the left hand winding of relay 412 to minus, operating relay 472 which looks in fromv minus through its contact 413 and right hand winding to conductor 359.

When the first high current impulse of the second round is transmitted, the operation starts again with relays 3 I 9 and 403 energizing as previously, etc. However, during the transmission of the second high current impulse, with relay 412 energized, a circuit-is closed from plus at conductor369, through contacts 4H of relay 430, M2, M3, M4, conductor M5, contact 33I of relay 3l'9, conductor 332, contact 419 of relay M2, the middle winding of relay 4H to minus. This winding sets up an equal and opposing flux with respectto the right hand holding winding neutralizing the flux of the relay 4H and causing it to release.

The operating circuit for relay 3553 during this round extends through contact 484 of relay 412 instead of 483 of relay M1. The rest of the operation is the same as for the first round.

men the printer has been reset after the second round, asimilar circuit is closed for relay 4'12, which can be traced from conductor 339 through contacts 4I I--4I3, 410, 483, and the middle winding of relay 412 to minus. Middle and right hand winding neutralize one another causing relay 412 to release.

Relay 3 I 5' again remains energized. The third round operates exactly the same way as the first, operating relay 4I'I during the second code impulse and relay 412 after resetting the printer. The fourth round operates the same way as the second, deenergizing relay 4H during the second code impulse and relay 412 at the end of the signal. The fifth and sixth rounds operate exactly as the first and second respectively so that relays 4H and 412 will be restored to the normal deenergized position at the end of the alarm signals transmitted by the transmitter.

After the printer has been operated for the last recording, the transmitter is kept operating until it reaches its home position where the master cam contacts of the transmitter are restored to the position shown on the drawing. Unless another-transmitter is already connected to the running line, the following line impulse will find the line open causing relays 233 and 2 It to releasein the same way as described above for relays I93 and I I6 for the supervisory circuit. Contact 223 opens, and then relay 305 releases the next time, opening contact 3I2, the circuit of thepulsing relays will be open as well as that of relay 3I5which releases.

Waterflow signals The .Waterflowtransmitter (Fig. 2) has a main motor and code wheel shaft and a geared shaft 17 somewhat as in Fig. 6 and is adapted for restoration signals somewhat as in Fig. 1. It is also provided with means for giving an extra impulse for tamper signals.

The shafts are geared to given one rotation of the geared shaft to each two rotations of the main or motor shaft. As will be later explained, the code Wheel gives waterflow signals during one and one-half rotations of the code wheel and a restoration signal during one-half rotation of the code wheel. This allows the transfer cam, which is preferably on the motor shaft, to operate to efiect transfer within a movement of 180 and 360 degrees from normal and requires that the master cam 14 operate the master switch at 270 and 360 degrees from normal. Hence the master cam is not symmetrical.

The waterfiow switch (Fig. 2) may be operated by a flow detector, as is well-known, and when operated a circuit is closed from plus available on the starting line ST through alarm contact 2| E! of the transfer cam 14' contact assembly, .through the normally open contact 209 of the W. F. switch and through thermostat heater winding 250 to negative available on the C line. The thermostat 25| starts to heat up. In case the W. F. switch is momentarily operated on account of water hammer in the piping system it does not stay closed long enough to permit the thermostat to operate, which will then again cool off when the flow detector restores its switch to normal, and nothing further happens; This arrangement thus prevents false alarms which would otherwise be caused by surges in the water pipes.

In case of -actual operation, the thermostat finally closes its contact 251 thereby energizing the transmitter from plus at the starting line through contacts 210, 25l, 2| l and the right hand magnet coil to negative available at the C line. Further operation for water fiow is the same as described above of Fig. 1.

In operating, the thermostat element 251 also moves a latch under the tip of pen spring 253 preventing it from later closing the associated contacts when the tooth of cam 254 has been rotated out of the way. This feature will be more specifically referred to when discussing tamper signals. At the end ofthe water flow signals, the master cam l4 restores the master switch to normal.

Water fiow signals are arranged for repeated operation and in the disclosed form of the system three signals are transmitted. Like supervisory transmitters, the waterfiow transmitters have to transmit a waterflow alarm signal and in addition a restoration signal when the waterfiow switch restores to normal. The code wheel is cut for the alarm code on one side and the restoration code on the other side. This restoration code is, however, identical with the code on the alarm side except that the second tooth of the first digit is cut off. The first digit on the alarm side consists of three teeth followed by 7 The first round of alarm signals is transmitted by the alarm'side of the code wheel. 'As just 18 mentioned, the first digit of the alarm code consists of three teeth followed by two spaces. The second tooth, as previously explained will operate relay 4lI, in the same way as above explained. The first stepping magnet operates three steps bringing the type of the words waterfiow alarm into printing position. When relay 3B4 releases following the transmission of the first low current or space impulse afterthe first digit, relay 43B is energized as usual, also relay 350 as for fire alarm signals. if contact 50'! is arranged to be closed in position 3 of the first typewheel, i. e., if waterfiow signals are to operate the gongs. The following impulse is again a low current impulse but relay 432 is not energized at this time as both contacts 331 of relay 315 and 349 of marginal relay 3-I9 are open. It is, however, operated through contact 349 of relay 3 l9 during the first high current impulse of the second digit,

starting the operation of the second stepping magnet. The second, third and fourth digits operate in the same way as for fire alarm signals. If relay 350 is energized, these digits will also operate gong 351. Relay 412 is likewise operated at the end of the printer operation.

The Waterflow transmitter is provided with gears which are arranged for a three-round alarm signal, i. e., one and one-half revolutions of the code wheel shaft. After the first alarm round has been recorded, the transmitter remains in operation and the second round is transmitted by the other side of the code Wheel which is identical to the first except the second tooth of the first digit is missing as in Fig. 12. This means that .the second line impulse will beof low current intensity and the circuit which causes relay 4|! to release on the second round of a fire alarm signal is ineffective due to contact 33I of relay 3l9 being open. However, when relay 334 subsequently releases, an impulse is transmitted to the first stepping magnet although contact 405 is open. This circuit can be traced from plus through contacts 321 of relay 304, 358 of relay 3I5, conductor 359. contacts 48| of relay 432, 482 of relay 4l0, conductor 40'! and. through the coil of the first stepping magnet PSI to minus so that the first stepping magnet will obtain three impulses as on the previous round. At the end of this signal, which otherwise operates the same as the first round, relay 412 is already energized and no change takes place as far as it is concerned. The transmitter continues to operate for its third round which again is transmitted by the same side of the code wheel as the first as in Fig. 11. The second code impulse is of high current intensity and causes relay 4!! to release as explained above for the second round of fire alarm signals. Relay 350 is operated during this round through contact 484 of relay 412 instead of contact 483. At the end of the third round, relay 412 is deenergized in the same way as for they second round of fire alarm signals. After completing its cycle, the transmitter will restore its master cam contacts to the normal condition and cause the control center relays to restore as previously explained.

It will be noticed that at the end of the third round of alarm, both relays 4|! and 412 are deenergized and ready for a new counting cycle.

Waterflow restoration signal When the waterflow stops, the waterflow switch returns to the normal position asillustrated. A starting circuit can then be traced from line ST through restoration contact 252 of therestoration cam which is now closed (as the transfer cam has been shifted 540 degrees, 3 rounds of signals having been transmitted) through the normally closed contacts 209 of the W. F. switch and the tamper switch through contact 2!! of the master switch and the right hand magnet to the C line. The code will now be transmitted by the restoration side of the code wheel as in Fig. 12. As will be recalled, the restoration code has a space following the first tooth. This means that relay ll? will not be operated during the tranmission of that particular impulse. However, as explained above, in connection with the second round of waterfiow alarm signals, the first stepping magnet will nevertheless obtain three impulses.

In addition, a circuit for the second stepping magnet is simultaneously closed. This can be traced from plus through contacts 321 of relay 304, 353 of relay 3|5', conductor 359, contacts 48!, see, 68?, 388 over conductor 439 and the coil of the second stepping magnet PS2 to minus. When the first printing magnet receives its third impulse, the second stepping magnet receives its second additional impulse, but through contact 486 of relay 423 instead of 485 of relay Mil. It will furthermore receive two additional impulses when magnet 3i! releases following the two low current space impulses after the first code digit. It will then be operated in the regular Way controlled by the second code digit. It will be seen that the second stepping magnet thus receives a total of four additional special impulses which with the addition of the three regular impulses later received, serve to advance the typewheel to the restoration position. The rest of the operation is the same as explained before. As both contacts 583 and 484 of relays 4H and 472 respectively are open, relay 350 is not operated, the pulsing speed is not changed nor are the gongs operated. When the printer is reset, the transmittercontinues to operate until it completes one half revolution. The master cam of the transmitter is cut in such a way that its contacts will resume their normal condition after the transmission of the restoration signal so that only one recording is obtained.

Water low tamper signals If someone opens the transmitter housing 2H3, the tamper switch is moved to contact 2 I l by any suitable means, for instance a spring 2H when the housing releases the vertical rod 2 l 2 pivoted to an extension of the switch transfer element. This causes a distinctive tamper signal. In that case the starting circuit can be traced from the ST line through contact 210, the normally open contact 2H1 of the tamper switch, contact 2i i, and the right hand motor winding to line C.

As the transmitter starts with the thermostat in its normal condition, the latch operated by the thermostat in case of waterflo'w is not in position to engage pen spring 253. After cam 254 has been rotated slightly, pen spring 253 drops oh the tooth and closes the associated contacts. It will be notice that the contacts of cam 255 are thereby connected in multiple with the coding contacts. The tooth of cam 255 is so arranged that the associated contacts are closed for one step immediately after the main coding contacts are opened at the end of the first digit of the code. An additional high current impulse is thus transmitted.

This causes the first typewheel of the printer to be advanced to the fourth positionbringing 20 WF Tamper into printing position. The rest of the operation isthe same as for waterflow alarm signals. Relay 350 and the gongs are not operated as cam operated contact 591 (Fig. 5) is open in position 4 of the first typewheel.

Waterflow tamper restoration When the tamper contacts are restored to the normally closed position, the transmitter is started as for waterfiow restoration signals. However. the additional impulse will also be added at the end of the first digit again causing the designation WF Tamper to be recorded on the printer, otherwise the recording is as explained above for waterfiow restoration signal.

Alarm signal precedence and non-interference and succession between alarm and supervisory circa-it If an alarm transmitter is actuated at or about the same time as a transmitter connected to the supervisory circuit, it will take precedence over it. In this case both relays H6 and 2H5, which may here be called precedence relays, will be energized. The operation of the pulsing relays will be started with rel'ay 30 i pulling up, then relay are and then relay 3M releasing. A circuit is now closed from plus through contacts 3l2,

3R3, of relays 3% and 384, respectively, conductor 3M, contact 223 of relay 2H5, conductor 22!; and through the coil of alarm master relay 325 and back Contact 3H5 of relay 3l5 to minus.

Supervisory master relay 3E5 cannot operate as contact 222 of relay 236, which supplies plus to contact I23 of relay H8 over conductor 3, is

open. r

If a transmitter on the supervisory circuit is actuated'first, it has to complete its signal in order to prevent interference but will let the alarm signal get in immediately after operating the printer. Assuming that while a transmitter is operating on the supervisory circuit, an alarm transmitter is actuated, relays 203 and H6 will be operated but relay 315 cannot be energized immediately as back contact 3|6-of relay 3I5 is open. When, however, relay 3|5 releases at the time of the printing operation, this contact closes again and relay 315 will operate as soon as the pulsing relays have started up and contact 3|2 of relay 3H5 closes. In this case the transmitter operated first on the supervisory circuit will not complete its cycle'until after all alarm signals have been cleared. it 'will then complete its remaining steps bringing the master cam back to the home position. This latter operation has been explained above in connection with the description of the supervisory transmitter.

Non-interference and saccessionof transmitters on the same circuit In case several transmitters are actuated on the same circuit at "or about the same time they willbe energized for'the initial starting impulse for which current is derived from the ST line. When 3E5 or 315' operate, the starting line will be simultaneously deenergized by the opening of back contact Bill or dill respectively; and the transmitters operate their master cam contacts to the running position. It will be seen that the transmitter located nearest to the on side of the R linewill be the only one to receive line impulses over the running line. After transmitting its signal and returning to the home position, this transmitter restores the running line to its normal condition and impulses will now 21 be directed to the second transmitter which" again prevents impulses from reaching transmitters Waiting further back on the line.

In case of this happening on the alarm circuit, the transmitters waiting will come in successively one after another without relay 3I5 releasing between. It has, however, been pointed out that the converting relays 4H and 412 are arranged to always complete a full cycle for each type of transmitter signal so as to be ready for a new counting cycle when a new transmitter starts to transmit.

Automatic trouble adjusting means and operation under trouble conditions In case of a break on the ST or C line, the corresponding relay I02 or 202 is deenergized and closes a circuit for the trouble lamp I01. Assuming that the break occurs on the supervisory circuit, for instance, the release of relay I02 or I01 or both, causes the deenergization of the normally energized upper Winding of adjusting relay I25. Relay- I25 releases and cannot be reoperated through this winding as contact I26 opens. This relay closes a circuitto the alarm buzzer 348 (right of Fig. 3) over conductor 360 by closing its back contact I36 (lower part of Fig. 1). The buzzer can be silenced by the operation of the corresponding silencing switch I36.

In this connection it may be pointed out that in case of operation with the circuit at normal, relays I02 and I01 are also deenergized when the circuit of the starting and running line is interrupted by relays H6 and 3I5. However, relay I25 is held energized, as a multiple circuit is closed by contacts I28 of relay I03 and I29 of relay IIB, also by contact 36I of relay 3I5 over conductor I30, keeping relay I25 energized during the transmission of the signal. After the release of relays I03, H6 and 3I5, relays I02 and I01 pick up again, closing the normal circuitfor relay I25. As there is a slight interval of time between the restoration of the line circuits and the closing of the make contacts of relay I02 and I01, relay I25 is equipped with a copper slug in order to keep it energized during this interval. The arrangement for the alarm circuit is identical.

Relay I25 releasing in case of a break of a line conductor connects the two ends of the ST lines together and the two ends of the C lines together, respectively by contacts I3I and I32 so that plus and minus polarity respectively is fed to both ends of the respective circuits at the same time. Assuming now thata break in all three wires is the case of the trouble,'which is the most severe condition, all transmitters connected to the circuit will still be able to obtain plus and minus polarity over the ST and C lines respectively for the initial starting step when actuated. A transmitter located between the break in the R line and its out side will operate in the usual way starting the operation of the system by operating relays I03 and I I6. If, however, the transmitter is located between the break and the in side of the R line, the closing of the armature contact will not operate starting relay I03 but operates relay H6 directly through the in side of the R line, contact I33, the right hand winding .of H6, contact I34 and the left hand winding of I I6 to plus. Relay II6 operates and closes the holding circuit for its left hand winding through contact IIB, resistor II9, over holding conductor H and through contact 303 to minus. A's contacts I34 and H0 are of the make-before-break type, the circuit of relay I I6 is never interrupted. Relay II 6 starts the operation of the pulsing relays in the usual way. It will be seen, however, that impulses are now transmitted through back contact I35, the right hand winding of relay H6 and back contact I33 over the in side of the R line, through the master cam contact I26 of the transmitter, its left hand magnet coil and through the C line to minus. This magnet is capable of operating the transmitter in the same way as the right hand one. Otherwise, however, the operation is the same as under normal conditions. The right hand winding of. relay H6 is similarly arranged as the left hand winding of I03 to hold relay II6 energized during the transmission of impulses, The left hand winding of II 6, similarly as to the right hand winding of I03, is deprived of current during the time of impulse transmission due to contacts 303 of relay 3I5, 323 of relay 305 and 324 of relay 304 being open. This arrangement again serves the purpose of clearing the control center equipment when the transmitter gets off the line.

Non-interference and succession on a circuit with line troubles The non-interference and successive operation is not affected by breaks in the ST and C lines. In case of a break in the-R line, transmitters operated simultaneously between the break and the out side of the R line will operate in the standard way. In case of transmitters operated simultaneously between the break and the in side of the R line, the one nearest to the in side will transmit its signal, first operating the relay I I6 or relay 2 I 6 directly as explained above. Otherwise the operation is the same as for normal conditions.

Simultaneous operation of transmitters on opposite sides of a break in the R line If two or more transmitters are simultaneously actuated, for starting, on opposite sides of a break in the R line, the transmitters located between the break and the out side of the R line will operate the I03 relay and II6 relay in succession. Transmitters located between the break and the in side of the R line will directly operate the H6 relay as explained before. As the H6 relay breaks the operating circuit of the I03 relay by its contacts' I04, the I03 relay may not have a chance to pick up if the transmitters are operated at exactly the same time. In that case, impulses will first be transmitted over the in side of the R line through back contact I35 of relay I03. After all the transmitters connected to that side of the circuit have transmitted their signal and the relay H6 is deenergized, relay I03 will be energized in series with the right hand coil of the transmitter nearest to the out side of the circuit. Relay I03 operates relay II6 which starts the operation. The transmitters located between the break and the out side of the circuit will then transmit their signals in succession. The same applies, of course, to relays 203 and 2I6 of the alarm circuit.

Restoration of circuit to normal after remedying trouble condition When the line breaks have been repaired, relays I02 and I0! or 202 and 201, respectively, will, nevertheless, not pick up since relay I25 or 225 first has to restore the line circuit to its normal condition. These relays are provided with another winding (the lower ones). These windings are connected to the minute impulse contact over conductor 3El and are energized once every minute. The next minute impulse following the repair of the line circuit will cause the corresponding relay I25 or 225 to pick up. It will then lock in through its contact I26 or 226, respectively, as soon as the relays I02 and I91 or 202 and 2&1 pick up. At the end of the minute impulse, relay I25 or 225 will then stay energized leaving the circuit at normal.

When relay I25 or 225 operates, a circuit is closed for the buzzer through make contact 121 or .221 and the normally open side of the associated silencing switch which reviously has been operated. By throwing the switch back to normal, the buzzer can be silenced. Relays H12 and H1! or 202 and 201 when operated, extinguish the lamp which was lighted when they released.

As a time impulse may come in during the transmission of a signal on an abnormal circuit, it must be prevented from causing interference by energizing the corresponding relay 125 or 225. This is obtained by connecting the restoring winding of these relays in series with a normally closed contact l3! or 231 respectively of the relays I it or 2; respectively which contact will then be open.

From the above it will be clear that, if a transmitter starts after the line has been repaired but before the minute impulse has restored relays l25 or 225 respectively, the signal will nevertheless be received without fail.

Ground supervision and operation with grounded Zines The system is operated from an ungrounded battery. However, the center of the battery is connected through contacts 353, 363' and the coil of relay 352 to ground. If a ground occurs on any of the line wires, this relay will be operated and closing its contact 354 light a lamp. By closing its make contact 365, the buzzer 348 is operated. It can be silenced by operation of the associated silencing switch. Operation of the system with a single ground onthe line Wires does not interfere with the normaloperation as the only other ground is through the very high resistance of relay 3:62. In addition this ground is removed as soon as relay 3I5 or 3:5 operate which then only leaves the accidental ground as the only one on the system. It will then have no effect at all.

If a ground occurs on two line wires simultaneously, it amounts to a short circuit between line wires and in most cases the line fuses will be blown except a ground on both the C line of the alarm and that of the supervisory circuit which will not interfere with the operation.

Automatic clearing after disarrangement of equipment If in working onthe relays etc. the serviceman should accidentally operate any of the relays, they will not lock in, as all locking circuits are arranged to function during operation only. Such accidental operation will, therefore, not affect a succeeding signal. Only the special alarm relay 343 can lock itselhfbut this is made noticeable immediately by the audible and visual signals and furthermore has no effect on succeeding signals. It can, of course, be restored in the usual way by operation of the acknowledgment key.

If the printer stepping magnets are manually operated, while the'equipme'nt is idle, relay432 will "be immediately energized from minus through the printer latch contact L, which will then be closed, over conductor M I, through contact 36 8 and 368' over conductor 310 and through the right hand winding of relay 432 to plus. This causes the operation of the printer release magnet RL through the same circuit as traced before. The release magnet restores all of the printer wheels to normal and opens the latch contact. The latter causes relay 32 to release again. It is therefore-impossible to leave any part of the equipment in a condition that it will intenfere with the proper reception of a subsequent signal.

Various modifications of the embodiment of the invention specifically described above will occur to those skilled in the art and may be made without departing from the scope of the invention as set forth in the appended claims,

What is claimed is:

1. A system comprising a series of transmitters, a main starting relay, a line normally connected at one end through the Winding of the starting .relay and to said transmitters, each transmitter comprising a motor and means for connecting said motor to said line to operate the relay, a second starting relay normally energized by the operation of the main starting relay, means set in operation by the operation of the second relay for sending motor current to the line, means set in operation by a line break to connect the other end of the line with the winding of the second starting relay to maintain the system in operative condition.

2. In combination, a series of transmitters, a control station including a source or current, a break detector relay and a main starting relay,

' a common line connected to the second pole of the source, a running line normally connected to the one pole of the source through the winding of the starting relay to said transmitters and the detector relay Winding to the second pole, each transmitter comprising a motor, means for conmeeting said motor between the common line and the running line for changing the current in the relay winding to operate the relay, a second starting relay set in operation by the operation of the main starting relay, means set in operation by the operation of the second relay for sending motoroperating current to the running line, means operated by the deenergization of said detector relay from line break to disconnect the running line from the'winding of said detector and connect'it in series with a winding of the second starting relay, and a periodic means adapted at intervals'to effect the restoration of the running line to normal if the second starting relay is un-- energized.

3. A system comprising a transmitter circuit, means for adjusting the system to circuit defect, means periodically automatically restoring the system to normal if the defect has been cured and transmission is not in progress.

4. In combination, a source of current, first and second groups of transmitters, normall ungrounded lines connecting the transmitters from the respective poles of the source, first and second master means associated with said groups respectively, each adapted to be energized by the starting of a transmitter of its associated set and to supply operating current to the transmitters during signaling, a grounded ground-detector connected to themidpart of said source, and means for'disconnect'ing the detector from said part if either of both master means are energized.

5. In a signaling system, a central station including a source of potential, a signaling circuit including a common loop circuit connected on one side to the negative side of said source, a starting 100p circuit connected on one side to the positive side of said source and on the other side to the free end of the common loop circuit, and a running 100p circuit connected across said source, at least one transmitter comprising motor coils, switching means for connecting a motor coil between the starting loop and the common loop, and a switch responsive to said coil for connecting at least a portion of said coil between the running loop and the common loop for increasing the current in the running loop, a main starting relay in the running loop for normally starting the transmitter in response to its connection, normally energized break detector relays connected in each of the loop circuits, a normally energized adjusting relay, contacts operated by the break detector relays for deenergizing said adjusting relay when a break occurs in the loops, contacts operated by the adjusting relay in case of breaks in the loops for connecting the ends of the starting loop and the ends of the common loop whereby negative polarity is connected to the common loop and positive polarity is connected to the starting loop, and the transmitter may operate the main starting relay if it is still connected thereto, an auxiliary starting relay, contacts operated by the adjusting relay for connecting the running loop to the auxiliary starting relay whereby the transmitter may operate if disconnected from the main 26 starting relay and periodic impulsing means connected to the adjusting relay for operating it to restore the loops to normal when the break therein is repaired.

6. In a signaling system, a central station including a source of potential, a signaling circuit to said source, at least one transmitter comprising a motor, switching means for connecting the motor to the circuit, a main starting relay in the circuit for normally starting the transmitter in response to its connection, normally energized break detector relays connected in the circuit, a normally energized adjusting relay, contacts op erated by the break detector relays for deenergizing said adjusting relay when a break occurs in the circuit, an auxiliary starting relay, contacts operated by the adjusting relay for connecting the circuit to the auxiliary starting relay whereby the transmitter may operate if disconnected from the main starting relay and periodic impulsing means connected to the adjusting relay for operating it to restore the loops to normal when the break therein is repaired.

MANFRED W. MUEHTER.

' file of this patent:

UNITED STATES PATENTS 

